Automatically point users at app store when update is ready?

[ckyourself]

I've seen this functionality before; an app update is available but maybe I haven't checked the appstore.app yet. At any rate the app say foo.app will prompt you while in app and say

"A new version for Foo.app is available! Want to goto the app store and download it?" (App Store) (Later)

Clicking app store takes you to the app store to download the new update, but effectively the app itself is aware of its own updates.

I'm assuming their app simply connects over a socket and pings their server or a simple script which replys with the current version which the developers maintain, then the app can determine if/when an update is avail and notify then.

Is this how this is done? Or is there a simple way w/o having to open an external facing http/other socket to a personal webserver...

-Matt

[paicolman]

Hi,

I implemented something similar in my last app, but I did it "the very dumb way"... I have a web server, in that server I have in a specific directory a file (in my case it's a PDF File, which the App tells the user being ready to download, but it could be something else)

So, the App knows the name of the file at some point in time. By sending an http request to <myServer>/<myDirectory>/myscript.php, the scripts returns the contents of that directory. The App compares the name of the pdf in that directory with the name of it's local pdf file. If the name has changed, it prompts the user. Stupid, but easy, and it works.

The drawback is: The App is always doing that small http request to the php script in the server, but the user barely notices it, and the couple of bytes flying around are not a problem.

Don't know exactly how to implement it to redirecting to the AppStore, but it could be something similar.

[smithdale87]

I'm assuming their app simply connects over a socket and pings their server or a simple script which replys with the current version which the developers maintain, then the app can determine if/when an update is avail and notify then.

I'd say this is a common solution.

[ckyourself]

Originally Posted by smithdale87

I'd say this is a common solution.

Sure, Here is my solution to this.

I made a version.txt on my webpage which contains the string "1.0.3" or whatever the current version on iTunes is.

I then can use the below function in my app delegate

- (void)checkWebForNewVersion {
    
    [NSThread detachNewThreadSelector:@selector(threadedCheckWebForNewVersion) toTarget:self withObject:nil];
    
}

- (void)threadedCheckWebForNewVersion {
    
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    
    NSLog(@"[UPDATE] Connecting to update server");
    
    NSData *verData = [[NSData alloc] initWithData:
                       [NSData dataWithContentsOfURL:
                        [NSURL URLWithString:@"http://lecturaapps.com/version.txt"]]];
    
    NSString *verStringNeedTrim = [[NSString alloc] initWithData:verData encoding:NSUTF8StringEncoding];
    NSString *verString = [[verStringNeedTrim stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] retain];
    [verStringNeedTrim release];
    
    if ([verString length] != 5) {
        NSLog(@"[UPDATE] Connection to update server failed. (invalid verstring length of %d)", [verString length]);
        [verData release];
        [verString release];
        return;
    }
    
    NSLog(@"[UPDATE] Connection to update server success. Version = %@", verString);
    
    NSString *localVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];
    
    // local
    NSMutableArray *leftFields  = [[NSMutableArray alloc] initWithArray:[localVersion  componentsSeparatedByString:@"."]];
    
    // web
	NSMutableArray *rightFields = [[NSMutableArray alloc] initWithArray:[verString componentsSeparatedByString:@"."]];
    
    while ([leftFields count] < [rightFields count]) {
        [leftFields addObject:@"0"];
    }
    
    while ([leftFields count] > [rightFields count]) {
        [rightFields addObject:@"0"];
    }
    
    BOOL showUpdateDialog = NO;
    
    for (int i = 0; i < [leftFields count]; i++) {
		NSComparisonResult result = [[leftFields objectAtIndex:i] compare:[rightFields objectAtIndex:i] options:NSNumericSearch];
		if (result != NSOrderedSame && result == NSOrderedAscending) {
            NSLog(@"[Update] User needs update");
            showUpdateDialog = YES;
            break;
        }
	}
    
    
    //NSLog(@"compared %@ vs %@", localVersion, verString);
    
    if (showUpdateDialog) {
        NSLog(@"[Update] Update needed! (have: %@, server: %@)", localVersion, verString);
        
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Update Available!"
                                                            message:[NSString stringWithFormat:@"Exhibit A version %@ now on App Store!", verString]
                                                           delegate:self
                                                  cancelButtonTitle:@"Later"
                                                  otherButtonTitles:@"App Store",nil];
        [alertView show];
        [alertView release];
        
        
    } else {
        NSLog(@"[Update] No update needed (have: %@, server: %@)", localVersion, verString);
    }
    
    [leftFields release];
    [rightFields release];
    [verData release];
    [verString release];
    
    
    [pool drain];
    
}

- (void)alertView:(UIAlertView *)av clickedButtonAtIndex:(NSInteger)buttonIndex {
	if (buttonIndex == 0) {
		NSLog(@"[Update] They canceled");
	} else {
		// direct them to our app in app store
	}
    
}